Ordovician Atlas

You have probably noticed that in past posts about the local paleontology, I have often linked specific fossil genera to an 'Ordovician Atlas' page. I thought I would share a little bit about this resource because I think it is a wonderful way to learn about the paleontology of the Cincinnati Arch.

This Ordovician Atlas is part of a collaborative NSF-funded initiative to produce digital atlases for multiple intervals of Earth history.

The Ordovician Atlas website is a series of interactive pages which allow you to search different fossil taxa that can be found in the strata along the Cincinnati Arch. Whether it be arthropods, brachiopods, echinoderms, cnidaria, mollusks or bryozoans, the Ordovician Atlas is a great resource for identifying taxa, identifying that strata you might find them in, ecological niches, descriptions or publication relevant to the taxa in question.


I know personally when dealing with fossils genera that I may be unfamiliar with, I always check the Ordovician Atlas to see if they have a listing. Below I have posted a few screenshots from the website to show some of the features present for individual genera, in this case Isotelus.

Example of the Isotelus page showing the Linnaean classification, geologic range and location map. 

Some of the pages shows these nice paleoecological diagrams depicting the range of habitats and organism may have lived. This image is for Isotelus maximus

These two images show the stratigraphic distribution of the general in question (Isotelus maximus) along with basic fossil descriptions.

Lastly, many of these pages will have a list of references and descriptions from those references, of the fossil in question.

The site contains more than just information about the various Cincinnatian genera. There is a page about the local geologic setting, the Richmondian Invasion (a person interest of mine) and various educational resources for the teachers among you. For those of you who like to go collecting, they have a page dedicated to listing good sites for doing just that!

I want to thank Dr. Alycia Stigall and the students in her lab for the great work they have put in and continue to put into this great resource.


I also would like to point you to this recent publication which discusses the program further.

Stigall, Alycia L., Jennifer E. Bauer, and Hannah-Maria R. Brame. "The Digital Atlas of Ordovician Life: digitizing and mobilizing data for paleontologists and the public." Estonian Journal of Earth Sciences 63.4 (2014): 312œ316.

Keep checking back for more additions to the Ordovician Atlas. If you are Twitter savvy, @PaleoDigAtlas is one source for updates to not just the Ordovician Atlas but the entirety of the 'Digital Atlas of Ancient Life' project.

Day of the Hypostome

Recently I was out in the field with members of our research group, studying the Lexington Limestone in Kentucky. It was one of those rare days in January where the sun was shining and temperatures were at a remarkable 12oC (~55oF)! Well we couldn't let a day like that past so we shook off the cobwebs and went out rid ourselves of some cabin fever.

It was at our first stop near the Rt 127/355 Junction in Kentucky, that one of the undergraduate students brought this slab over to me.

The obvious feature that stands out of course is the light brown 1/2 ring shape outlining the cephalon (head) of an Isotelus trilobite. Isotelus parts are pretty common in the Ordovician of the Cincinnati Arch, sort of the local weed organism which shows up everywhere.We marveled for a moment at the size of the beastie, Isotelus is known to be quite large (largest species is Isotelus rex at ~70cm long - see Palaeocast interview with Dr. Rudkin or the Original Paper) and I was about to hand it back when the real interesting part of the specimen popped out at me, part of the hypostome was present in situ.

The hypostome is the hard mouthpart of a trilobite believed to be used in feeding. It is located on the underside or ventral side of the trilobite. I have a wonderful GIF generated of one of my committee members demonstrating how these hypotstomes may have been used to scoop up worms, but he holds the fate of my future graduation partially in his hands so I will have to refrain from sharing!

Now finding a hypostome is not uncommon by any means, I had found one just a few minutes earlier that was in even better condition. (See my tweet highlighting another hypostome)

The interesting thing is to see the hypostome in situ with all of the cephalon (minus the margin) removed. 

Anyways I thought it was a cool little specimen and I will be certainly adding it to my future teaching collection. Please keep checking here for more posts on interesting fossils/strata we've found and for thoughts on equally interesting papers!